宁夏羊胃肠道线虫对现行驱虫药的抗药性调查

采用粪便虫卵减少试验对宁夏地区所属灵武、贺兰、盐池、吴忠、中宁、中卫、永宁和银川市郊8个县(市)的12个绵羊场、6个山羊场进行了丙硫苯咪唑和阿维菌素抗药性的随机调查。结果表明:在用丙硫苯咪唑调查的10个绵羊场和6个山羊场中,虫卵减少率在95%以下和95%的置信域下限在90%以下的有山羊场2个、绵羊场2个,证明对丙硫苯咪唑有抗药性;1个绵羊场和1个山羊场的虫卵减少率是96.3%、95.9%,但95%置信域的下限在90%以下,具有抗药性可疑;山羊群中丙硫苯咪唑的抗药性为33.3%,绵羊群为20.0%。用同样的方法调查了1个山羊场和5个绵羊场(其中有4个羊场曾执行了丙硫苯咪唑的试验),查出1个山羊场和1个绵羊场对阿维菌素具有抗药性可疑,其虫卵减少率分别为97.3%和95.5%,置信域下限在90%以下。揭示了宁夏地区羊消化道线虫对现行驱虫药的抗药状态,为今后防治提供了依据。

Investigation on resistance of gastrointestinal nematodes in sheep and goats to anthelmintics in Ningxia, China

To understand the current situation of resistance of gastrointestinal nematodes in sheep and goats to current anthelmintics,an investigation was carried out by faecal egg count reduction tests on 12 sheep farms and 6 goat farms in 7 counties including Lingwu,Helan,Yanchi,Wuzhong,Zhongning,Zhongwei and Yongning,and Yinchuan Prefecture in Ningxia,China.The resistance to albendazole(ALB) was examined on 10 sheep farms and 6 goat farms.Four out of them had values less than 95% of faecal egg count reduction(FECR) percentage and the 95%-confidence limit was less than 90%,accoun-ting for 25%(4/16) of all the examined farms,demonstrating the presence of ALB resistant strains in the above farms.On 1 sheep farm and 1 goat farm,the percentage of FECR were 96.3% and 95.9%,respectively,but the 95%-confidence limits were less than 90%,so they were suspected to be developing resis-tance against ALB.In two goat farms and 2 sheep farms out of 4 farms,resistance to ALB in worm populations was detected,indicating that the prevalence rate of ALB resistance in goat flocks was 33% and 20% in sheep flocks.Using the same method,the investigation of avermectin(AVM) resistance on 1 goat farm and 5 sheep farms showed that there was the presence of suspected resistant strains against AVM on 1 goat farm and 1 sheep farm.Their percentage of FECR were 97.3% and 95.5%,respectively,and the 95%-confidence limits were less than 90%.These findings revealed the status of resistance of gastrointestinal nematodes in sheep and goats to anthelmintics in north-western China to some extent,which provided foundation for the controlling of nematodes in sheep and goats.